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Angelique Duet is a spin-off of the first Angelique game and one of the titles made to celebrate Koei's twentieth year anniversary. According to Ruby Party commentary, this title answered popular fan demand for an option to play as the first protagonist's rival, Rosalia. The Premimum Box edition (PlayStation and Sega Saturn only) includes a special musicbox, bookmarks of the Sacred Guardians, and another colored comic book.